Once the Outlook database is successfully rebuilt, try launching Outlook 2011 againģ) If that doesn’t work, reboot the Mac and try launching Outlook 2011 again Therefore, if you have this issue (Outlook 2011 for Mac not starting up), you could try the following steps:ġ) First, just reboot the Mac and then try launching Outlook 2011Ģ) If that doesn’t work, try rebuilding the Outlook 2011 database following Carl’s instructions in this forum post but, beforehand, make a separate backup of the plagued Outlook Identity (normally “Main Identity”) from the Finder, just in case.

That is a possibility that I can’t easily verify at this time. Now I am thinking: Maybe a reboot was all that was needed in my case which did not necessarily require rebuilding the database. However, rebooting the Mac afterwords did the trick. At first, this did not work for me (but read on): Outlook 2011 would still refuse to start up (just showing a brief splash screen and then aborting, same as before) even AFTER successfully rebuilding the Outlook database following the instructions here.